Question

Factor completely 2x3 + x2 - 18x - 9

Answer 1

Factor the following:
2 x^3 + x^2 - 18 x - 9

Factor terms by grouping. 2 x^3 + x^2 - 18 x - 9 = (2 x^3 + x^2) + (-18 x - 9) = x^2 (2 x + 1) - 9 (2 x + 1):
x^2 (2 x + 1) - 9 (2 x + 1)

Factor 2 x + 1 from x^2 (2 x + 1) - 9 (2 x + 1):
(2 x + 1) (x^2 - 9)

x^2 - 9 = x^2 - 3^2:
(2 x + 1) (x^2 - 3^2)

Factor the difference of two squares. x^2 - 3^2 = (x - 3) (x + 3):

Answer:  (x - 3) (x + 3) (2 x + 1) thus the Answer is C.

Answer 2

Answer:

(x - 3) (x + 3) (2 x + 1) thus the Answer is C.

Step-by-step explanation: